(1) Field of the Invention
The invention relates to a water filter cartridge and to a tank having a filter cartridge, as well as to a line-connected connecting head for a water filter cartridge with a connecting element for plugging into a tank, a filter cartridge, an appliance or a water filter connecting head. More particularly the invention pertains to a connecting element which is part of a tank, filter cartridge, appliance or a connecting head which has a polygonal contour.
(2) Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
A water tank to hold a liquid, to hold water in the case of kitchen equipment, coffee machines or espresso machines, is provided in various kitchen equipment and machines, for example in water filter jugs, water boilers, coffee or espresso machines, in which case a filter cartridge can be inserted into the tank, in order to prepare the water before processing in the machine or before consumption. Known filter cartridges have an outlet in the lower area, through which outlet the water is supplied to the associated machine or to a storage or reservoir vessel. In this case, the water is passed via a preferably gravimetrically operated filter bed, and is passed via a connection of the filter cartridge to a corresponding connection of the water tank, into the machine or some other reservoir and storage vessel.
For reliable operation of the kitchen equipment and machine, it is of major importance that a filter cartridge with defined filter parameters is used. An incorrect filter cartridge will result in the machine being supplied with inadequately or incorrectly prepared water, which can lead to negative effects, for example inadequate taste and/or smell optimization, calcium reduction or the like, or even to machine defects. The machine control system is, for example, not able to initiate the intended servicing intervals at the correct time, as when using a filter cartridge of the correct type, if such a filter cartridge is not actually used, however. When using inadequate filter cartridges, problems arise not only in the operational reliability of the machine but also in the question of the guarantee, etc. It is therefore of major importance to ensure that only permissible filter cartridges are ever used.